lttng-filter-specialize.c

   1 /*
   2  * lttng-filter-specialize.c
   3  *
   4  * LTTng modules filter code specializer.
   5  *
   6  * Copyright (C) 2010-2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; only
  11  * version 2.1 of the License.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include "lttng-filter.h"
  24
  25 int lttng_filter_specialize_bytecode(struct bytecode_runtime *bytecode)
  26 {
  27         void *pc, *next_pc, *start_pc;
  28         int ret = -EINVAL;
  29         struct vstack _stack;
  30         struct vstack *stack = &_stack;
  31
  32         vstack_init(stack);
  33
  34         start_pc = &bytecode->data[0];
  35         for (pc = next_pc = start_pc; pc - start_pc < bytecode->len;
  36                         pc = next_pc) {
  37                 switch (*(filter_opcode_t *) pc) {
  38                 case FILTER_OP_UNKNOWN:
  39                 default:
  40                         printk(KERN_WARNING "unknown bytecode op %u\n",
  41                                 (unsigned int) *(filter_opcode_t *) pc);
  42                         ret = -EINVAL;
  43                         goto end;
  44
  45                 case FILTER_OP_RETURN:
  46                         ret = 0;
  47                         goto end;
  48
  49                 /* binary */
  50                 case FILTER_OP_MUL:
  51                 case FILTER_OP_DIV:
  52                 case FILTER_OP_MOD:
  53                 case FILTER_OP_PLUS:
  54                 case FILTER_OP_MINUS:
  55                 case FILTER_OP_RSHIFT:
  56                 case FILTER_OP_LSHIFT:
  57                 case FILTER_OP_BIN_AND:
  58                 case FILTER_OP_BIN_OR:
  59                 case FILTER_OP_BIN_XOR:
  60                         printk(KERN_WARNING "unsupported bytecode op %u\n",
  61                                 (unsigned int) *(filter_opcode_t *) pc);
  62                         ret = -EINVAL;
  63                         goto end;
  64
  65                 case FILTER_OP_EQ:
  66                 {
  67                         struct binary_op *insn = (struct binary_op *) pc;
  68
  69                         switch(vstack_ax(stack)->type) {
  70                         default:
  71                                 printk(KERN_WARNING "unknown register type\n");
  72                                 ret = -EINVAL;
  73                                 goto end;
  74
  75                         case REG_STRING:
  76                                 insn->op = FILTER_OP_EQ_STRING;
  77                                 break;
  78                         case REG_S64:
  79                                 if (vstack_bx(stack)->type == REG_S64)
  80                                         insn->op = FILTER_OP_EQ_S64;
  81                                 else
  82                                         insn->op = FILTER_OP_EQ_DOUBLE_S64;
  83                                 break;
  84                         case REG_DOUBLE:
  85                                 if (vstack_bx(stack)->type == REG_S64)
  86                                         insn->op = FILTER_OP_EQ_S64_DOUBLE;
  87                                 else
  88                                         insn->op = FILTER_OP_EQ_DOUBLE;
  89                                 break;
  90                         }
  91                         /* Pop 2, push 1 */
  92                         if (vstack_pop(stack)) {
  93                                 ret = -EINVAL;
  94                                 goto end;
  95                         }
  96                         vstack_ax(stack)->type = REG_S64;
  97                         next_pc += sizeof(struct binary_op);
  98                         break;
  99                 }
 100
 101                 case FILTER_OP_NE:
 102                 {
 103                         struct binary_op *insn = (struct binary_op *) pc;
 104
 105                         switch(vstack_ax(stack)->type) {
 106                         default:
 107                                 printk(KERN_WARNING "unknown register type\n");
 108                                 ret = -EINVAL;
 109                                 goto end;
 110
 111                         case REG_STRING:
 112                                 insn->op = FILTER_OP_NE_STRING;
 113                                 break;
 114                         case REG_S64:
 115                                 if (vstack_bx(stack)->type == REG_S64)
 116                                         insn->op = FILTER_OP_NE_S64;
 117                                 else
 118                                         insn->op = FILTER_OP_NE_DOUBLE_S64;
 119                                 break;
 120                         case REG_DOUBLE:
 121                                 if (vstack_bx(stack)->type == REG_S64)
 122                                         insn->op = FILTER_OP_NE_S64_DOUBLE;
 123                                 else
 124                                         insn->op = FILTER_OP_NE_DOUBLE;
 125                                 break;
 126                         }
 127                         /* Pop 2, push 1 */
 128                         if (vstack_pop(stack)) {
 129                                 ret = -EINVAL;
 130                                 goto end;
 131                         }
 132                         vstack_ax(stack)->type = REG_S64;
 133                         next_pc += sizeof(struct binary_op);
 134                         break;
 135                 }
 136
 137                 case FILTER_OP_GT:
 138                 {
 139                         struct binary_op *insn = (struct binary_op *) pc;
 140
 141                         switch(vstack_ax(stack)->type) {
 142                         default:
 143                                 printk(KERN_WARNING "unknown register type\n");
 144                                 ret = -EINVAL;
 145                                 goto end;
 146
 147                         case REG_STRING:
 148                                 insn->op = FILTER_OP_GT_STRING;
 149                                 break;
 150                         case REG_S64:
 151                                 if (vstack_bx(stack)->type == REG_S64)
 152                                         insn->op = FILTER_OP_GT_S64;
 153                                 else
 154                                         insn->op = FILTER_OP_GT_DOUBLE_S64;
 155                                 break;
 156                         case REG_DOUBLE:
 157                                 if (vstack_bx(stack)->type == REG_S64)
 158                                         insn->op = FILTER_OP_GT_S64_DOUBLE;
 159                                 else
 160                                         insn->op = FILTER_OP_GT_DOUBLE;
 161                                 break;
 162                         }
 163                         /* Pop 2, push 1 */
 164                         if (vstack_pop(stack)) {
 165                                 ret = -EINVAL;
 166                                 goto end;
 167                         }
 168                         vstack_ax(stack)->type = REG_S64;
 169                         next_pc += sizeof(struct binary_op);
 170                         break;
 171                 }
 172
 173                 case FILTER_OP_LT:
 174                 {
 175                         struct binary_op *insn = (struct binary_op *) pc;
 176
 177                         switch(vstack_ax(stack)->type) {
 178                         default:
 179                                 printk(KERN_WARNING "unknown register type\n");
 180                                 ret = -EINVAL;
 181                                 goto end;
 182
 183                         case REG_STRING:
 184                                 insn->op = FILTER_OP_LT_STRING;
 185                                 break;
 186                         case REG_S64:
 187                                 if (vstack_bx(stack)->type == REG_S64)
 188                                         insn->op = FILTER_OP_LT_S64;
 189                                 else
 190                                         insn->op = FILTER_OP_LT_DOUBLE_S64;
 191                                 break;
 192                         case REG_DOUBLE:
 193                                 if (vstack_bx(stack)->type == REG_S64)
 194                                         insn->op = FILTER_OP_LT_S64_DOUBLE;
 195                                 else
 196                                         insn->op = FILTER_OP_LT_DOUBLE;
 197                                 break;
 198                         }
 199                         /* Pop 2, push 1 */
 200                         if (vstack_pop(stack)) {
 201                                 ret = -EINVAL;
 202                                 goto end;
 203                         }
 204                         vstack_ax(stack)->type = REG_S64;
 205                         next_pc += sizeof(struct binary_op);
 206                         break;
 207                 }
 208
 209                 case FILTER_OP_GE:
 210                 {
 211                         struct binary_op *insn = (struct binary_op *) pc;
 212
 213                         switch(vstack_ax(stack)->type) {
 214                         default:
 215                                 printk(KERN_WARNING "unknown register type\n");
 216                                 ret = -EINVAL;
 217                                 goto end;
 218
 219                         case REG_STRING:
 220                                 insn->op = FILTER_OP_GE_STRING;
 221                                 break;
 222                         case REG_S64:
 223                                 if (vstack_bx(stack)->type == REG_S64)
 224                                         insn->op = FILTER_OP_GE_S64;
 225                                 else
 226                                         insn->op = FILTER_OP_GE_DOUBLE_S64;
 227                                 break;
 228                         case REG_DOUBLE:
 229                                 if (vstack_bx(stack)->type == REG_S64)
 230                                         insn->op = FILTER_OP_GE_S64_DOUBLE;
 231                                 else
 232                                         insn->op = FILTER_OP_GE_DOUBLE;
 233                                 break;
 234                         }
 235                         /* Pop 2, push 1 */
 236                         if (vstack_pop(stack)) {
 237                                 ret = -EINVAL;
 238                                 goto end;
 239                         }
 240                         vstack_ax(stack)->type = REG_S64;
 241                         next_pc += sizeof(struct binary_op);
 242                         break;
 243                 }
 244                 case FILTER_OP_LE:
 245                 {
 246                         struct binary_op *insn = (struct binary_op *) pc;
 247
 248                         switch(vstack_ax(stack)->type) {
 249                         default:
 250                                 printk(KERN_WARNING "unknown register type\n");
 251                                 ret = -EINVAL;
 252                                 goto end;
 253
 254                         case REG_STRING:
 255                                 insn->op = FILTER_OP_LE_STRING;
 256                                 break;
 257                         case REG_S64:
 258                                 if (vstack_bx(stack)->type == REG_S64)
 259                                         insn->op = FILTER_OP_LE_S64;
 260                                 else
 261                                         insn->op = FILTER_OP_LE_DOUBLE_S64;
 262                                 break;
 263                         case REG_DOUBLE:
 264                                 if (vstack_bx(stack)->type == REG_S64)
 265                                         insn->op = FILTER_OP_LE_S64_DOUBLE;
 266                                 else
 267                                         insn->op = FILTER_OP_LE_DOUBLE;
 268                                 break;
 269                         }
 270                         vstack_ax(stack)->type = REG_S64;
 271                         next_pc += sizeof(struct binary_op);
 272                         break;
 273                 }
 274
 275                 case FILTER_OP_EQ_STRING:
 276                 case FILTER_OP_NE_STRING:
 277                 case FILTER_OP_GT_STRING:
 278                 case FILTER_OP_LT_STRING:
 279                 case FILTER_OP_GE_STRING:
 280                 case FILTER_OP_LE_STRING:
 281                 case FILTER_OP_EQ_S64:
 282                 case FILTER_OP_NE_S64:
 283                 case FILTER_OP_GT_S64:
 284                 case FILTER_OP_LT_S64:
 285                 case FILTER_OP_GE_S64:
 286                 case FILTER_OP_LE_S64:
 287                 case FILTER_OP_EQ_DOUBLE:
 288                 case FILTER_OP_NE_DOUBLE:
 289                 case FILTER_OP_GT_DOUBLE:
 290                 case FILTER_OP_LT_DOUBLE:
 291                 case FILTER_OP_GE_DOUBLE:
 292                 case FILTER_OP_LE_DOUBLE:
 293                 case FILTER_OP_EQ_DOUBLE_S64:
 294                 case FILTER_OP_NE_DOUBLE_S64:
 295                 case FILTER_OP_GT_DOUBLE_S64:
 296                 case FILTER_OP_LT_DOUBLE_S64:
 297                 case FILTER_OP_GE_DOUBLE_S64:
 298                 case FILTER_OP_LE_DOUBLE_S64:
 299                 case FILTER_OP_EQ_S64_DOUBLE:
 300                 case FILTER_OP_NE_S64_DOUBLE:
 301                 case FILTER_OP_GT_S64_DOUBLE:
 302                 case FILTER_OP_LT_S64_DOUBLE:
 303                 case FILTER_OP_GE_S64_DOUBLE:
 304                 case FILTER_OP_LE_S64_DOUBLE:
 305                 {
 306                         /* Pop 2, push 1 */
 307                         if (vstack_pop(stack)) {
 308                                 ret = -EINVAL;
 309                                 goto end;
 310                         }
 311                         vstack_ax(stack)->type = REG_S64;
 312                         next_pc += sizeof(struct binary_op);
 313                         break;
 314                 }
 315
 316                 /* unary */
 317                 case FILTER_OP_UNARY_PLUS:
 318                 {
 319                         struct unary_op *insn = (struct unary_op *) pc;
 320
 321                         switch(vstack_ax(stack)->type) {
 322                         default:
 323                                 printk(KERN_WARNING "unknown register type\n");
 324                                 ret = -EINVAL;
 325                                 goto end;
 326
 327                         case REG_S64:
 328                                 insn->op = FILTER_OP_UNARY_PLUS_S64;
 329                                 break;
 330                         case REG_DOUBLE:
 331                                 insn->op = FILTER_OP_UNARY_PLUS_DOUBLE;
 332                                 break;
 333                         }
 334                         /* Pop 1, push 1 */
 335                         next_pc += sizeof(struct unary_op);
 336                         break;
 337                 }
 338
 339                 case FILTER_OP_UNARY_MINUS:
 340                 {
 341                         struct unary_op *insn = (struct unary_op *) pc;
 342
 343                         switch(vstack_ax(stack)->type) {
 344                         default:
 345                                 printk(KERN_WARNING "unknown register type\n");
 346                                 ret = -EINVAL;
 347                                 goto end;
 348
 349                         case REG_S64:
 350                                 insn->op = FILTER_OP_UNARY_MINUS_S64;
 351                                 break;
 352                         case REG_DOUBLE:
 353                                 insn->op = FILTER_OP_UNARY_MINUS_DOUBLE;
 354                                 break;
 355                         }
 356                         /* Pop 1, push 1 */
 357                         next_pc += sizeof(struct unary_op);
 358                         break;
 359                 }
 360
 361                 case FILTER_OP_UNARY_NOT:
 362                 {
 363                         struct unary_op *insn = (struct unary_op *) pc;
 364
 365                         switch(vstack_ax(stack)->type) {
 366                         default:
 367                                 printk(KERN_WARNING "unknown register type\n");
 368                                 ret = -EINVAL;
 369                                 goto end;
 370
 371                         case REG_S64:
 372                                 insn->op = FILTER_OP_UNARY_NOT_S64;
 373                                 break;
 374                         case REG_DOUBLE:
 375                                 insn->op = FILTER_OP_UNARY_NOT_DOUBLE;
 376                                 break;
 377                         }
 378                         /* Pop 1, push 1 */
 379                         next_pc += sizeof(struct unary_op);
 380                         break;
 381                 }
 382
 383                 case FILTER_OP_UNARY_PLUS_S64:
 384                 case FILTER_OP_UNARY_MINUS_S64:
 385                 case FILTER_OP_UNARY_NOT_S64:
 386                 case FILTER_OP_UNARY_PLUS_DOUBLE:
 387                 case FILTER_OP_UNARY_MINUS_DOUBLE:
 388                 case FILTER_OP_UNARY_NOT_DOUBLE:
 389                 {
 390                         /* Pop 1, push 1 */
 391                         next_pc += sizeof(struct unary_op);
 392                         break;
 393                 }
 394
 395                 /* logical */
 396                 case FILTER_OP_AND:
 397                 case FILTER_OP_OR:
 398                 {
 399                         /* Continue to next instruction */
 400                         /* Pop 1 when jump not taken */
 401                         if (vstack_pop(stack)) {
 402                                 ret = -EINVAL;
 403                                 goto end;
 404                         }
 405                         next_pc += sizeof(struct logical_op);
 406                         break;
 407                 }
 408
 409                 /* load field ref */
 410                 case FILTER_OP_LOAD_FIELD_REF:
 411                 {
 412                         printk(KERN_WARNING "Unknown field ref type\n");
 413                         ret = -EINVAL;
 414                         goto end;
 415                 }
 416                 /* get context ref */
 417                 case FILTER_OP_GET_CONTEXT_REF:
 418                 {
 419                         printk(KERN_WARNING "Unknown get context ref type\n");
 420                         ret = -EINVAL;
 421                         goto end;
 422                 }
 423                 case FILTER_OP_LOAD_FIELD_REF_STRING:
 424                 case FILTER_OP_LOAD_FIELD_REF_SEQUENCE:
 425                 case FILTER_OP_GET_CONTEXT_REF_STRING:
 426                 case FILTER_OP_LOAD_FIELD_REF_USER_STRING:
 427                 case FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE:
 428                 {
 429                         if (vstack_push(stack)) {
 430                                 ret = -EINVAL;
 431                                 goto end;
 432                         }
 433                         vstack_ax(stack)->type = REG_STRING;
 434                         next_pc += sizeof(struct load_op) + sizeof(struct field_ref);
 435                         break;
 436                 }
 437                 case FILTER_OP_LOAD_FIELD_REF_S64:
 438                 case FILTER_OP_GET_CONTEXT_REF_S64:
 439                 {
 440                         if (vstack_push(stack)) {
 441                                 ret = -EINVAL;
 442                                 goto end;
 443                         }
 444                         vstack_ax(stack)->type = REG_S64;
 445                         next_pc += sizeof(struct load_op) + sizeof(struct field_ref);
 446                         break;
 447                 }
 448                 case FILTER_OP_LOAD_FIELD_REF_DOUBLE:
 449                 case FILTER_OP_GET_CONTEXT_REF_DOUBLE:
 450                 {
 451                         if (vstack_push(stack)) {
 452                                 ret = -EINVAL;
 453                                 goto end;
 454                         }
 455                         vstack_ax(stack)->type = REG_DOUBLE;
 456                         next_pc += sizeof(struct load_op) + sizeof(struct field_ref);
 457                         break;
 458                 }
 459
 460                 /* load from immediate operand */
 461                 case FILTER_OP_LOAD_STRING:
 462                 {
 463                         struct load_op *insn = (struct load_op *) pc;
 464
 465                         if (vstack_push(stack)) {
 466                                 ret = -EINVAL;
 467                                 goto end;
 468                         }
 469                         vstack_ax(stack)->type = REG_STRING;
 470                         next_pc += sizeof(struct load_op) + strlen(insn->data) + 1;
 471                         break;
 472                 }
 473
 474                 case FILTER_OP_LOAD_S64:
 475                 {
 476                         if (vstack_push(stack)) {
 477                                 ret = -EINVAL;
 478                                 goto end;
 479                         }
 480                         vstack_ax(stack)->type = REG_S64;
 481                         next_pc += sizeof(struct load_op)
 482                                         + sizeof(struct literal_numeric);
 483                         break;
 484                 }
 485
 486                 case FILTER_OP_LOAD_DOUBLE:
 487                 {
 488                         if (vstack_push(stack)) {
 489                                 ret = -EINVAL;
 490                                 goto end;
 491                         }
 492                         vstack_ax(stack)->type = REG_DOUBLE;
 493                         next_pc += sizeof(struct load_op)
 494                                         + sizeof(struct literal_double);
 495                         break;
 496                 }
 497
 498                 /* cast */
 499                 case FILTER_OP_CAST_TO_S64:
 500                 {
 501                         struct cast_op *insn = (struct cast_op *) pc;
 502
 503                         switch (vstack_ax(stack)->type) {
 504                         default:
 505                                 printk(KERN_WARNING "unknown register type\n");
 506                                 ret = -EINVAL;
 507                                 goto end;
 508
 509                         case REG_STRING:
 510                                 printk(KERN_WARNING "Cast op can only be applied to numeric or floating point registers\n");
 511                                 ret = -EINVAL;
 512                                 goto end;
 513                         case REG_S64:
 514                                 insn->op = FILTER_OP_CAST_NOP;
 515                                 break;
 516                         case REG_DOUBLE:
 517                                 insn->op = FILTER_OP_CAST_DOUBLE_TO_S64;
 518                                 break;
 519                         }
 520                         /* Pop 1, push 1 */
 521                         vstack_ax(stack)->type = REG_S64;
 522                         next_pc += sizeof(struct cast_op);
 523                         break;
 524                 }
 525                 case FILTER_OP_CAST_DOUBLE_TO_S64:
 526                 {
 527                         /* Pop 1, push 1 */
 528                         vstack_ax(stack)->type = REG_S64;
 529                         next_pc += sizeof(struct cast_op);
 530                         break;
 531                 }
 532                 case FILTER_OP_CAST_NOP:
 533                 {
 534                         next_pc += sizeof(struct cast_op);
 535                         break;
 536                 }
 537
 538                 }
 539         }
 540 end:
 541         return ret;
 542 }